P34806NLOO/RR Title: Prefab thermal housing unit configured to be placed on the ground spaced from a building and comprising a heat pump, hydro module and water buffer means.
FIELD OF THE INVENTION The present invention relates to prefab thermal housing units that are configured to be placed on the ground spaced from a building, of a type comprising at least a heat pump having an evaporator and a condenser, with a compressor and an expansion valve installed between them, and water connections that are configured to be connected to water ducts leading towards a domestic network of the building, like a central heating network and/or hot water network to be used for consumption, showering, bathing, and the like.
BACKGROUND TO THE INVENTION A thermal housing unit to be assembled together at a distance from a building is known from EP-0.032.381. The outer walls of this unit are designed for absorption of solar energy and of thermal energy contained in the air and in rain. For that the roof is formed by a solar collector, whereas water ducts are provided alongside the walls. The housing unit comprises multiple floor levels, with on a first floor level a heat pump, an energy converter in the form of an additional heating device, and an energy storage device. The additional heating device is fueled out of a storage container that is embedded in the ground underneath the unit in between foundations on top of which the unit is destined to be placed. At an intermediate floor level a rain water reservoir is provided, whereas on an upper floor level a ventilator and an evaporator are installed.
During operation environmental air gets drawn by the ventilator to flow along the water ducts towards the evaporator. The evaporator is able to take thermal energy out of the air and then the heat pump exchanges this thermal energy with water that can get distributed through a heating network of the building via suitable water ducts that are provided between the thermal housing unit and a heating network inside the building.
A disadvantage hereof is that the construction and operation of the thermal housing unit leaves to be improved. It is such complex, heavy and high that it is difficult to accurately place in its entirety, that is to say with the floors, side walls and roof already fully made and assembled together, and with the various installation parts already pre-positioned and operatively connected with each other inside them. In practice this shall mean that the unit frequently shall be installed on site. Furthermore the various floor levels are difficult to access
2. for maintenance of the various installation parts, in particular during bad weather. Performing such operations under safe prescribed conditions seems impossible. Furthermore it is disadvantageous that the additional heating device is fuel-driven, and despite being placed inside the housing, still may make a lot of noise, whereas its outlet gases are polluting for the environment. Also it is noted that the fuel storage container underneath the housing unit is difficult to access and forms a fire and explosion risk.
A prefab thermal housing unit is known from DE-32.29.197. Herein a concrete housing is shown for a fuel-engine driven heat pump. The housing comprises three prefabricated concrete housing components, that is to say a lower basin, an upper basin and a cover plate. When placed on top of each other, a lower and upper installation space are formed. With this the lower installation space is fully closed and houses the fuel-engine, an outlet gas treatment device, and a compressor and condenser of the heat pump, whereas the upper installation space forms an air flow-through tunnel and houses an evaporator and ventilator of the heat pump that are delimited downstream and upstream by silencers through which the air must pass.
The evaporator is able to take thermal energy out of the air and then via the condenser exchange this thermal energy with water that can get distributed through a heating network of the building via suitable ducts or pipes that can be provided between the prefab thermal housing unit and the heating network inside the building.
A disadvantage hereof also is that the construction and operation of the prefab thermal housing unit leaves to be improved. On the one hand it is such heavy and high that it is difficult to place in its entirety, that is to say with the heavy concrete housing components already pre-placed on top of each other and with the various installation parts already pre- positioned inside them. In practice the heavy concrete housing components therefore presumably frequently shall need to be assembled on top of each other while the installation parts get installed on site. Also the heavy concrete housing components are difficult to fit into each environment with respect to style and colour.
Furthermore, during use, both the upper and lower installation spaces are difficult to access for maintenance of the various installation parts, in particular during bad weather. Performing such operations under safe prescribed conditions seems not possible. Yet another disadvantage is that the extraction of thermal energy from the air only has use when the building actually needs heating. Furthermore it is disadvantageous that the fuel-engine, despite being placed inside the concrete housing, still makes a lot of noise and causes all kinds of vibrations that needs to be dampened, and, despite its outlet gases receiving after- treatment, still is polluting for the environment. Also it is noted that the fuel-engine needs to
-3- be fed with fuel and for that the prefab thermal housing unit needs an additional fuel connection.
BRIEF DESCRIPTION OF THE INVENTION The present invention aims to overcome those disadvantages at least partly or to provide a usable alternative. In particular the present invention aims to provide an improved thermal housing unit that can be truly efficient in terms of thermal energy exchange and that is economic and quick to prefabricate and place.
According to the present invention this aim is achieved by a prefab thermal housing unit that is configured to be placed on the ground spaced from a building according to claim 1. The unit comprises a floor, housing walls and a roof that together delimit an indoor installation space. Furthermore the unit comprises a heat pump and water connections that are configured to be connected to water ducts of a network of the building. According to the inventive thought the heat pump, also sometimes referred to as an outside part of a heat pump, is configured for exchanging thermal energy between outside air and a heat transfer medium. A hydro module, also sometimes referred to as an inside part of a heat pump, is provided that comprises a heat exchanger that is configured for exchanging thermal energy between the heat transfer medium and water that is to be used for hot water consumption in the building and/or for heating/cooling of the building. Water buffer means are provided that are connected to the hydro module, and that are configured for storing amounts of said water that are to be used for hot water consumption in the building and/or for heating/cooling of the building. The heat pump is installed outside of the indoor installation space, and the hydro module and the water buffer means are installed inside the indoor installation space.
Thus advantageously a thermal housing unit is obtained that can be truly prefabricated on a desired location and then transported in its entirety to an aimed site spaced from but near a building to be heated or cooled and/or to be provided with hot tapping water for consumption purposes, while at a same time making it possible to deal with rapidly increasing market demands for silent, efficient and preferably also gasless thermal energy exchange solutions both for new construction projects as well as for renovation projects.
The outside-placed heat pump and inside-placed hydro module make it possible to not only extract thermal energy from the environmental air and use that directly or indirectly via a respective one of the water buffer means for heating the building, but if desired also make it possible to deliver thermal energy to the environmental air and use that directly or indirectly via the same or another respective one of the water buffer means for cooling the building, and if desired also make it possible to extract thermal energy from the environmental air and use
-4- that directly or indirectly via another respective one of the water buffer means as hot consumption water that comes out of a tap in the building.
By installing the heat pump outside the indoor installation space it is able to operate more efficiently in terms of heat exchange, whereas the installation of the hydro module and water buffer means inside the indoor installation space makes it possible to protect them against weather influences, insulate them against heat and cold and noise and make them easily accessible for maintenance, while at a same time keep the entire prefab unit lightweight and compact.
The hydro module for example may comprise a plate-type heat exchanger, through or along which the heat transfer medium coming from the heat pump flows and along or through which the water to be heated or cooled flows. Furthermore, the hydro module may also comprise a transportation pump, in particular an adaptive rpm controlled transportation pump, for actively transporting water into or out of the water buffer means. With adaptive it is meant that it is configured to automatically be able to respond to a required amount of water inside the building. Further, the hydro module may comprise a controllable multi-way valve that is configured for having controllable amounts of water that has been heated or is to be cooled by the heat exchanger flow into or out of respective ones of the water buffer means and/or for having controllable amounts water that has been heated by the heat exchanger flow out of or towards a hot water distribution network inside the building and/or for having controllable amounts water that has been heated or is to be cooled by the heat exchanger flow out of or towards a heating/cooling network inside the building. Thus all kinds of combinations can be made, and a true optimization of the heat pump, not only for heating but if desired also for coaling, can be obtained via the hydro module. For this a programmable control unit can be provided.
In a preferred embodiment the water buffer means comprise a tank for buffering an amount of heated water ready for heating the building, and a boiler for buffering an amount of heated water, preferably at a constant temperature, ready for tapping hot water by consumers inthe building. Owing to the multi-purpose buffering, advantageously the capacity of the heat pump can be used more optimally. The preparing of hot water for consumption purposes, including showering and bathing, now can also profit from the extracting of thermal energy by the heat pump out of the environmental air. Furthermore the preparing of the hot water for consumption purposes now advantageously also can take place inside the prefab thermal housing unit at a distance from the building where it is to be used. This saves space inside the building and makes those required installation parts also easier accessible for maintenance.
-5- The tank preferably has a buffering capacity of between 50-300 litres.
The boiler preferably has a buffering capacity of between 150-500 litres.
In a preferred further or alternative embodiment a surplus heater can be provided that is also installed inside the indoor installation space, and that is configured for additionally heating the water that is to be used for hot water consumption in the building and/or for heating/cooling of the building.
Thus advantageously always high enough temperatures can be reached for the water before it gets buffered in the respective ones of the water buffer means and/or before it gets transported via the water connections towards the building.
For the hot water consumption purpose this can help to prevent legionella.
For the heating network purpose this can help to quicker be able to heat the building to a desired temperature during cold days and extreme weather.
The surplus heater preferably is an electric heater.
In a preferred further or alternative embodiment at least the hydro module and the water buffer means, and if provided also the surplus heater, can be positioned in the indoor installation space alongside the housing walls, while leaving free a corridor between them towards an entrance door that is provided in the housing walls.
The exact relative positions of the installation parts can be chosen such that there is enough free space for a maintenance person to stand in the technical area inside the unit, and thus be able to properly perform the required operations according to the regulations.
The door can be a single or double door that is lockable for unauthorized entrance.
In a preferred further or alternative embodiment the unit further may comprise a load bearing frame with upper and lower beams connected to each other via columns, and for example made out of galvanized steel, and panels that are mounted against the load bearing frame and that form said housing walls for delimiting said indoor installation space.
The working with the panels make it possible to easily adapt them to each environment where the unit needs to be placed in terms of style, material, colour and the like.
In addition thereto the panels can advantageously be formed by insulation sandwich panels, in particular with a plate shaped insulation core and inside and outside shielding plates.
Those are both strong and lightweight and well able to keep the technical area in the indoor installation space isolated for noise and against too high or low outside temperatures.
In an advantageous embodiment the core of such sandwich panels then can be a foamed core, like a polyurethane foam.
This gives good insulation capacities to the panels.
In addition or in the alternative, the shielding plates of such sandwich panels then can be metal plates, like steel plates, that then in particular can be coated or painted with a protective layer.
This gives good rigidity to the panels.
In another example the shielding plates of such sandwich
-6- panels can also be plastic plates, like recycled plastic plates, that then can be moulded with all kinds of textures, like for example wood patterns, and/or that can be made in all kinds of colours. This gives good flexibility for the designer and a good combination between rigidity, durability and pricing.
In a preferred further or alternative embodiment the load bearing frame may include hoisting and/or lifting provisions, like rings connected to its upper beams and/or insertion holes inside or between its lower beams, that are configured for picking and placing the entire unit at once with for example a forklift or crane.
In a preferred further or alternative embodiment an outdoor installation space can be provided sideways of the indoor installation space, that is also covered by the roof, that is delimited on one side by one of the housing walls, and on the other sides by shielding elements, wherein the shielding elements together are configured to let the outside air flow into and out of the outdoor installation space, and wherein the heat pump then is installed inside the outdoor installation space. This provides for a protected positioning of the heat pump there where it can function optimally. Advantageously no special air flow-through tunnel or the like at an increased floor level has to be provided inside the indoor installation space of the housing unit itself. This helps to keep the prefab thermal housing unit relative compact and lightweight.
In addition thereto the shielding elements preferably can be mounted detachable against the load bearing frame. In this way no special entrance door has to be provided, whereas the heat pump still is accessible for maintenance or the like.
Further in addition thereto the shielding elements can be formed by spaced apart planks. This gives the air freedom to flow into and out of the outdoor installation space along the heat pump installed therein, while at a same time giving the prefab thermal housing unit an attractive outer appearance.
In another advantageous embodiment the shielding elements that shield the outdoor installation space can also be made air-permeable themselves, like being provided with large numbers of through holes.
In addition thereto it is then also possible to have the shielding elements that shield the outdoor installation space configured for sound-damping. In an advantageous embodiment this is done by using sandwich panels of which the core is made out of a sound- absorbing yet air-permeable material, and of which inside and outside shielding plates are provided with the through holes. Those are both strong and lightweight and well able to keep the technical area in the outdoor installation space isolated for noise. In an advantageous embodiment the core of such sandwich panels then can be a mineral wool. This gives good
-7- isolation capacities to the panels. In addition or in the alternative, the shielding plates of such sandwich panels then can be perforated metal plates, like steel plates, that then in particular can be coated or painted with a protective layer. This gives good rigidity to the panels. In another example the shielding plates of such sandwich panels can also be perforated plastic plates, like recycled perforated plastic plates, that then can be moulded with all kinds of textures, like for example wood patterns, and/or that can be made in all kinds of colours. This gives good flexibility for the designer and a good combination between rigidity, durability and pricing.
In addition thereto it possible to have specifically those in-between housing walls/panels that extend between the indoor and outdoor installation space also configured for sound-absorption, such that noise-reflection of sounds coming from the heat pump there against is prevented. In an advantageous embodiment this can be done by using sandwich panels of which the core is made out of a sound-absorbing material, like said abovementioned mineral wool, and of which the outside shielding plates then can be provided with through holes. It can also be done by providing sound-absorbing material mats or the like directly against the outdoor installation space directed sides of those in-between housing walls/panels.
In a preferred further or alternative embodiment the floor may also be formed by an insulation sandwich panel, in particular with a load distribution plate on top of it. Thus the unit is well insulated against cold and moisture from out of the ground. The load distribution plate can be a wooden plate, for example a plywood plate that is coated for protection, for example with epoxy and/or that is provided for safety with an antiskid profile.
In a preferred further or alternative embodiment the roof may also be formed by an insulation sandwich panel, in particular with a protective roofing layer on top of it. Thus the unit is also properly insulated against weather influences. The protective roofing layer can be an EPDM. It is however also possible to place other layers on top of the roof, like a sedum or solar panel(s).
Further preferred embodiments of the invention are stated in the dependent subclaims.
-8-
DETAILED DESCRIPTION OF THE DRAWINGS The invention shall now be explained in more detail below by means of describing an exemplary embodiment in a non-limiting way with reference to the accompanying drawings, in which: - Fig. 1 shows a schematic sectional view seen from above of a prefab thermal housing unit according to the invention; - Fig. 2 shows a schematic see-through view of fig. 1; - Fig. 3a-c show a top, front and back view of the unit of fig. 1 and 2; and - Fig. 4 shows a variant of various components and connections there between to be placed inside an indoor installation space of a housing unit according to the invention. In fig. 1-3 the entire prefab thermal housing unit has been given the reference numeral
1. The unit 1 comprises a load bearing frame 2 that comprises an upper and lower rectangular frame of horizontally orientated galvanized steel profiles, also referred to as beams 3, that are connected with each other on their corners by means of vertically orientated galvanized steel profiles, also referred to as corner columns 4. The front and back side beams 3 of the lower frame are provided with spaced sets of holes 5 that are configured for forks of a fork lift truck to be inserted therein. On top of the lower frame a floor 8 is formed that here comprises insulation sandwich panels 8a and epoxy coated plywood plates 8b with antiskid profile. On top of the upper frame a roof 10 is formed that here comprises an insulation sandwich panel 10a and a protective EPDM roofing layer 10b glued against it. At an eccentric position between the corner columns 4, a front and back side intermediate column 12 are provided, that here are also formed by vertically orientated galvanized steel profiles that are connected to the upper and lower frames. The intermediate columns 12 divide the load bearing frame 2 in a left and a right section. The left section forms a so-called outdoar installation space 14 whereas the right section forms a so-called indoor installation space 15. The installation spaces 14, 15 are together covered by the roof 10. They each have their own insulation sandwich panel portion 8a and epoxy coated plywood plate portion 8b that lie at a same level. The indoor installation space 15 has insulation sandwich panels 17° as housing walls 17 that are mounted against the load bearing frame 2. At the front side two door columns 18 are provided, that here are also formed by vertically orientated galvanized steel profiles that are connected to the upper and lower frames. Between those door columns 18 a lockable door 19 is foreseen.
-9- The outdoor installation space 14 is provided sideways of the indoor installation space 15 and as such is delimited on one side by the insulation sandwich panels 17’ of one of the housing walls 17. On three other sides it is shielded by spaced apart wooden planks. The planks serve as shielding elements 21 that shield of the outdoor installation space 14 while leaving it in open connection with the outside air.
Inside the outdoor installation space 14, an electric inverter controlled heat pump 25 is installed that works in either direction to provide heating or cooling by having a heat transfer medium that flows through it, also referred to as refrigerant, exchange thermal energy with the outside air. For this the heat pump 25 employs a reversing valve to reverse the flow of heat transfer medium from a compressor through a condenser and evaporator. Furthermore the heat pump 25 here is of a type in the range of 3-15kW, and having a low noise level of less than 38db(A) at a distance of 5 meter. The heat pump 25 is placed on an elevation 26 such that any defrosting water may easily flow away and such that during freezing no ice- formation underneath it can occur.
Inside the indoor installation space 15, a hydro module 30, a boiler 31, atank 32, a surplus heater 33 and water connections 34 are installed. Each of them are placed in a corner section of the indoor installation space 15, with the tank 32 and the boiler 31 placed alongside the insulation sandwich panels 17’ of the housing walls 17 in the backside left and right corner sections, with the hydro module 30 placed alongside the insulation sandwich panels 17’ of the housing walls 17 in the frontside left corner section, and with the surplus heater 33 and water connections 34 placed alongside the insulation sandwich panels 17’ of the housing walls 17 in the frontside right corner section. Thus the indoor installation parts are installed such that they leave a corridor free for a maintenance person to stand protected underneath the roof 10 right behind the door 19.
The water connections 34 can be connected to water ducts that extend towards a building, like a house, apartment or office. The prefab thermal housing unit 1 can be delivered together with an adapter plate for the required to be connected water ducts towards the building. Thus those water ducts can be laid in advance in such a way that they automatically correspond to with the water connections 34 of the later to be placed prefab thermal housing unit 1.
The hydro module 30 is connected to the heat pump 25 and comprises a heat exchanger that is configured for exchanging thermal energy between the heat transfer medium and a flow of water.
This flow of water through the hydro module 30 can in the first place be used directly as circulation water that is destined for heating/cooling rooms inside the building by means of
-10- radiators, floor heating or the like. For this the circulation water is to be heated or cooled in the hydro module to then be transported towards the tank 32 where it can be kept at a certain temperature. From out of the tank 32 this hot or cold circulation water then can be transported via the water connections 34 towards the building.
The flow of water through the hydro module 30 can in the second place also be used to heat up fresh water that is destined for human consumption inside the building by means of hot water taps, shower heads or the like. For this the flow of water through the hydro module 30 can be run through a heat exchanger, like for example a spiral, that is provided inside the boiler 31 where it can exchange heat to a supply of fresh tapping water that is to be kept at a temperature of for example between 70-90 degrees Celsius. From out of the boiler 31 this fresh hot tapping water then can be transported via the water connections 34 towards the building.
The hydro module 30 comprises a control unit, a controllable multi-way valve and a reversible transportation pump that together are configured for actively controlling the rates and directions of the water flow between the heat exchanger inside the boiler 31 respectively the tank 32.
The surplus heater 33 is provided as additional or backup heater, and can be used to have the fresh and/or circulation water additionally heated whenever the heat pump is unable to deliver enough thermal energy.
Fig. 4 shows a variant of the various components to be placed inside the indoor installation space. Same components, like the hydro module 30, the boiler 31, a tank 32 and the water connections 34, have been given same reference numbers. In this variant now also a loading module 40 is provided that is configured to be placed in between the boiler 31 and the hydro module 30, and that comprises its own heat exchanger. During use, relative cold tapping water from the boiler 31 then may flow through the heat exchanger inside the loading module 40. Inside this heat exchanger the tapping water then indirectly gets heated by the heated flow of water coming from the hydro module 30. The advantage hereof is that no distinctive heat exchanger has to be placed inside the boiler 31, such that more water buffer space is obtained, and such that occurrence of cold zones inside the boiler 31 is avoided. Yet another advantage is that a legionella program can be run more efficiently, for example by being able to periodically bring the entire content of the boiler 31 to a sufficiently higher temperature via the external heat exchanger inside the loading module 40, without a relative cold tapping water layer being able to remain at the bottom of the boiler 31.
Furthermore, in fig. 4 now a distinctive expansion vessel 41 is shown, that is configured to deal with changing volumes of the amount of circulation water depending on its temperature and for that is connected to the tank 32.
-11- Besides the shown and described embodiment, numerous variants are possible. For example the dimensions and shapes of the various parts can be altered. Also it is possible to make combinations between advantageous aspects of the shown embodiments. Instead of using lightweight insulation sandwich panels, other kinds of wall, roof and/or floor materials can be used, like for example wood, stone-like materials or (recycled) plastics. Instead of using wooden planks, other kinds of shielding elements can be used, like for example ones of stone-like materials or (recycled) plastics, or perforated (sandwich) panels with air-permeable sound-absorption materials integrated therein,. Furthermore, it is also possible to use other numbers and types of water buffer means as well as for other purposes. If cooling is not to be foreseen, then an irreversible type of heat pump can also be provided. The indoor installation space preferably also may get provided with ventilation, heating and an electricity service wall socket. Furthermore the indoor installation space may also be provided with other kinds of installation components that are prone to make some noise, like for example a heat recovery unit, like a mechanical ventilation heat recovery, and/or a PV-inverter for solar panels, such that those components also get well protected inside the prefab thermal housing unit and dampened for noise at a distance from a building to be lived or worked in.
It should be understood that various changes and modifications to the presently preferred embodiments can be made without departing from the scope of the invention, and therefore will be apparent to those skilled in the art. It is therefore intended that such changes and modifications be covered by the appended claims.